The measurement of the properties of optical devices is of high interest for the telecommunications community. Temporal modulators are routinely used to carve trains of optical pulses and encode data via amplitude or phase modulation. Devices such as semiconductor optical amplifiers are also used for amplification and processing of optical waves. The accurate description of the properties of a device, such as the amplitude and phase response versus the electrical or optical drive signal or the dependence between transmission and phase, is important to the understanding of the properties of the generated optical signals.